1. Field of the Invention
The present invention relates to a compressor system, and in particular to the compressor drive system for a compressor used to supercharge internal combustion engines.
2. Description of the Related Art
Internal combustion engines are supercharged in order to raise the power or to increase the torque. The improvement through supercharging is achieved through improving the efficiency by increasing the quantity of air in the cylinder. It is known to employ the procedure known as self-supercharging, in which for example a turbocharger driven by the exhaust gases or a compressor driven by means of toothed belts is used, or else to employ the concept of external turbocharging, in which the charge volume, i.e., the quantity of air in the cylinder is increased by means of an auxiliary module, for example by means of a compressor driven by an electric motor. That enables more air, and thus also more oxygen, to be pumped into the combustion chambers of the cylinder, thus enabling the engine power to be increased without increasing the displacement.
At the same time, it is also known to operate mechanically driven compressors with variable rotational speed between the internal combustion engine and the supercharger, that is, the compressor.
Starting from that basis, an object of the present invention is to provide a compact and efficient drive unit for a compressor for supercharging a internal combustion engine, one that can optionally be switched off.